Southern Shore Spleenwort

Botanical name: Asplenium scleroprium
Synonyms: Asplenium aucklandicum, Asplenium scleropium
Common name(s): Southern Shore Spleenwort

Plant facts:
A rare southern coastal fern endemic to New Zealand, adapted to exposed maritime environments and subantarctic climates. This species is recognised by its leathery dark green fronds, sharply toothed pinnae, and strong association with windswept rocky coastlines.

Natural habitat:
Occurs naturally on exposed coastal cliffs, rocky headlands, sea-facing slopes, and coastal shrubland margins.

Growing environment:
Full sun to partial shade, Coastal exposure, Free-draining soils & Wind tolerant.
Thrives in cool maritime conditions with excellent drainage and regular air movement.

Endemic distribution:
Endemic to New Zealand.
Found in the southern South Island, Stewart Island/Rakiura, Snares Islands, Chatham Islands, and Auckland Islands.

Height:
Approximately 0.15–0.5 m tall

Width:
Forms dense clumps approximately 0.3–0.8 m across

Uses:

• Coastal revegetation
• Subantarctic-themed gardens
• Rock wall plantings
• Fern collections
• Coastal restoration projects
• Exposed maritime landscaping

Appearance:

Growth habit:
A robust tufted evergreen fern forming dense clumps from stout fleshy rhizomes.

Fronds:
Fronds are thick, leathery, dark green to blue-green, and strongly adapted to exposed coastal environments.

Leaflets:
Pinnae are narrow ovate with regularly deep toothed margins and tapering pointed tips.

Rhizome and stems:
Rhizomes are stout and densely covered with dark brown scales. Stipes and rachises are brown beneath and green above with dense narrow scales.

Sori:
Long sori develop beneath the fronds and extend towards the margins within the leaflet indentations.

Ecology:
A specialised southern coastal fern frequently growing alongside Asplenium obtusatum on windswept cliffs and exposed maritime headlands.

Associated habitats:
Often associated with coastal shrubland, rocky sea cliffs, seabird-influenced habitats, and subantarctic vegetation communities.

How to grow:
Best grown in cool coastal conditions with free-draining soil and good airflow. Suitable for exposed rockeries, coastal gardens, and maritime fern collections.

Propagation:
Propagated from spores or division of established clumps. Slow growing but hardy once established.

Garden value:
A distinctive and highly specialised coastal fern valued for its leathery toothed fronds and tolerance of extreme maritime conditions. Excellent for cool coastal gardens and collectors of southern New Zealand flora.